Methine dyestuffs



United States Patent 3,255,204 METHINE DYESTUFFS Roderich Raue, Leverkusen, Werner Muller, Cologne, Oskar Weissel, Krefeld-Uerdingen, Germany, and Max Coenen, deceased, late of Gruiten, Germany, by Ruth Coenen, Gerda Coenen, Barbara Coenen, and Helia 3 Claims. 61. 260-319) The present invention relates to novel methine dyestutfs. This invention is a continuation in-part of our copending application 835,181, filed August 21, 1959, now abandoned.

It is an object of the present invention to provide novel methine dyestuffs which are distinguished by very good fastness properties,.especially. excellent fastness to light. Another object of this invention is to provide a process for the dyeing and printing with said novel methine dyestutfs of materials made from synthetic polyamides and polyurethanes as well as from polyesters, preferably polyethyleneterephthalates. A further object is the provision of dyed and printed materials of the above-mentioned class which possess very good fastness properties.

The new methine dyestuffs of this invention correspond to the formula In this formula R-stands for a lower alkyl group, preferably for CH or C H R stands for hydrogen or lower alkyl, R denotes hydrogen or CN and R stands for a radical of the cyano acetic acid, cyano acetic acid lower alkyl ester, cyano acetic acid substituted lower alkyl ester series, such as cyano acetic acid hydroxy lower alkyl ester and cyano acetic acid cyano lower alkyl ester, a cyano acetic acid amide, bound at the carbon atom in adjacent position to the CN group, or R stands for the radical of malonic acid dinitrile; the radicals R, R R and R must not contain sulfonic acid groups.

The dyestuffs are obtainable, for instance, by condensing in preferably alkaline medium 2-methylene-5-carbo lower alkoxy indoline-w-aldehydes which are disubstituted in 3-position by methyl groups and which may contain in l-position lower alkyl substituents, with sulfonic acid group-free cyano acetic acid or its functional derivatives or nitriles, esters or amides indicated above. The reaction of the starting components is carried out in the presence or in the absence of dissolving or diluting agents, with the addition of preferably alkaline catalysts, e.g., by refluxing the reaction components for several hours. Suitable dissolving and diluting agents are those which, under the conditions of the condensation reaction, act indifferent and which are able to sufiiciently dissolve the reaction components; there may be mentioned for instance, methanol, ethanol, dioxane, tetrachloromethane, chlorobenzene and toluene.

As alkaline condensation agents there can be used, e.g.

3,255,204 Patented June 7, 1966 pyridine, diethylamine, potassium hydroxide, sodium hybe used for instance, cyano acetic acid esters, such as the methyl, ethyl, propyl and butyl ester, cyano acetic acid- ,B-cyanoethyl ester, cyano acetic acid-fi-hydroxyethylester, cyano acetic acid amide, methylamide, dimethylamide, ethylamide, fl-hydroxy ethylamide, diethylamide, propylamide, -'y-methoxy propylamide, y-dimethylamino propylamide, butylamide, anilide, benzylamide, and malonic acid dinitrile.

The novel methinedyestuffs yield valuable dyeings and prints on textile materials such as fibres, filaments, ribbons etc., made from synthetic polyamides and polyurethanes as well as fromaromatic polyesters, preferably polyethyleneterephthalates.

The dyestuffs are applied onto the above-mentioned materials accordingto methods which are known as such, for instance, from an aqueous dispersion at temperatures of between about 60 C. to about 100 C. The dyestuifs can also be used for dyeing in the so-called spinning process by adding them to a spinning solution before spinning. The dyeings and prints which are obtained by the improved process of the present invention are distinguished by brilliancy and excellent fastness to light.

The following examples are given for the purpose of illustrating the invention without, however, limiting it thereto.

Example 25.9 parts by weight of 1,3,3-trimethyl-5-carbomethoxy- 2-methyleneindoline-w-aldehyde and 11.3 parts by weight of cyano acetic acid ethylester are heated to the boil at reflux condenser with 100 parts'by volume of ethanol for 10 minutes, whereupon the aldehyde component partly dissolves. 2 parts by volume of piperidine are then added dropwise and the reaction mixture is further boiled. After 10 minutes a clear solution is obtained which is further refluxed, for two hours. On cooling down, the dyestufl crystallizes in almost quantitative yield. It is filtered with suction and washed with ethanol (M.P. 174175 C.).

20 parts by Weight of the dyestuff thus obtained are kneaded with parts by weight of a condensation product of formaldehyde and naphthalene sulfonic acid and with little water, until fine division. The paste is then dried at 50 C. in vacuo.

Yarn made from e-caprolactam is introduced at 50 C. into a dye-bath which contains per litre 0.66 gram of the dyestutf dispersion described above, and 0.5 gram of a condensation product of formaldehyde and naphthalene sulfonic acid. The liquor-to-goods ratio is 35:1. The dye-bath is heated to C. within 30 minutes and dyeing continued at this temperature for one hour. The yarn is subsequently rinsed with water and dried. One obtains a greenish-yellow shade having excellent fastness to light.

Fibres of polyethyleneterephthalate are dyed in a dyebath having a liquor-to-goods ratio of 30:1, and containing 5 grams of cresotic acid methylester and 1.3 grams of dispersion of the dyestufi' which was prepared in accordance with this example and converted into a finely divided state by the method indicated in Example 1; the pH value of the dye-bath was adjusted to 4.5 by the addition of sulfuricaci-d. Within 20 minutes the initial temcomponents used in this example, the components listed in.

the following table are used for the preparation of the methine dyestuifs:

4 3. The dyestufi of the formula Aldehyde component Methylene compound M.P. of the Shade of the dye dyestufi, C. on polyamide fibres 1,3,3-trimethyl-5-carbomethoxy-2-methylene- Cyano acetic acid butylester 165-167 Grecnish yellow.

indoline-m-aldehyde.

1,3,3-trimethyl-5-carbomcthoxy-Z-rnethylene- Cyano acetic acid-B-hydroxy ethyl-amidc 280-282 Do.

indoline-w-aldehyde.

1,3,3-trimethyl-fi-carbometl1oxy-2-methylcne- Gyano acetic acid-'y-methoxy-propylamidc 180-182 Do.

indoline-w-aldehyde.

l-ethyl-3,3-dimethyl-5-carboethoxy-2-methyl- Cyano acetic acid ethylester 160-163 Do.

eneindoline-w-aldehyde.

1,3,3-trimethyl-5-carbomethoxy-2methylene-+ Malonic acid dinitrilc 152-155 D0.

indolinc-w-aldehyde.

1,3,3-trimethyl-5-carbomethoxy-Z-methylene- Oyano acetic acid-B-cyano-ethylester 215-218 Do.

indoline-w-aldehyde.

1,3,3-trimethylecarbomethoxy-2-methylene- Malonic acid dinitrile 227-229 Do.

indoline-w-cyan-w-aldehyde.

2. A dyestufi of the formula I R0 00 o-om I OH;

wherein R stands for lower alkyl and R stands for cyano lower alkyl.

References Cited by the Examiner UNITED STATES PATENTS Coenen Chemische Beri-chte, vol. 82, pages 66-72 Coenen et al., Zeitschrift by Elektrocheme, vol. 57,

40 pages 785-795 (1953).

Colour Index, vol. 3, 2nd Edition, 1956, pages 3401- 3404, Charley & Pickersgill Ltd., Leeds, England.

oooonrloN 409,350 551,825

GEN

5/1953 Edwards 260---3l9 12/1954 Kendall et a1. 260-240 FOREIGN PATENTS 4/ 1934 Great Britain. 11/1956 Belgium.

OTHER REFERENCES NICHOLAS S. RIZZO, Primary Examiner.

IRVING MARCUS, WALTER A. MODANCE,

Examiners.

EGON E. BERG, MARY OBRIEN, Assistant Examiners. 

2. A DYESTUFF OF THE FORMULA 